@charset "utf-8";

* {
    margin: 0;
    padding: 0;
}

body {
    background-color: #ccc;
}

ul,
ol {
    list-style: none;
}

a {
    text-decoration: none;
}

/*二级导航条 */
.menu {
    width: 1200px;
    height: 60px;
    margin: 20px 25px;
    background-color: rgb(20, 121, 215);
}

.menu::after {
    content: '';
    display: block;
    clear: both;
}

.menu-item {
    float: left;
    padding: 0 20px;
    width: 120px;
    line-height: 60px;
    text-align: center;
}

.menu-item a {
    display: block;
    color: #fff;
}

.menu .sub-menu {
    position: absolute;
    width: 120px;
    height: 0;
    overflow: hidden;
    background-color: rgb(255, 170, 0);
    transition: all 0.5s;
}

.menu-item:hover .sub-menu {
    height: 360px;
}